Locking mechanisms of various types have long been used for a wide variety of applications. A locking mechanism generally has two states, a locked state, whereby the locking mechanism restrains an article, and an un-locked state, whereby the article is not restrained. An actuation member is generally is operable to switch the locking mechanism between the locked and un-locked states. Different types of locking mechanisms and actuation members may be optimal for different types of applications. For instance, it may be desirable for a locking mechanism to self-engage and automatically switch between the un-locked state and the locked state under certain circumstances, such as the position or orientation of the article, for example.
In one example, U.S. Pat. No. 5,123,664 describes a locking mechanism for removably coupling an ice skate runner to a skate shoe without manual manipulation of the locking mechanism. Where a definition or use of a term in a reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies to this disclosure and the definition of that term in the reference does not apply to this disclosure. In U.S. Pat. No. 5,123,664, a user positions a slot of the runner over a pin on the skate shoe. Stepping into the skate shoe pushes a locking end of the runner into a snap-locking mechanism on the shoe, and the user's weight causes the snap-locking mechanism to engage and lock the locking end of the runner in place. In order to unlock the snap-locking mechanism and remove the runner, the user manually engages a release that disengages the snap-locking mechanism.
In some applications, it is desirable that an article can be released without having to engage a manual release. Self-disengaging locking mechanisms have been developed that are configured to un-lock under certain conditions. U.S. Pat. No. 5,042,856 describes a locking mechanism for a dumpster lid that uses a counterweight such that when the dumpster is moved from an upright to an inverted position, i.e. when being emptied by a garbage collection truck, gravity acts on the counterweight and unlocks the lid. Other similar examples known in the art include hooks that release at a certain orientation, or moving elements that are brought into an actuation position by gravity when in a certain orientation, such as, for example, the rolling sphere in the gravity locking articulation of a briefcase that unlocks when the briefcase is properly oriented, as described in U.S. Pat. No. 5,369,843. Some locking mechanisms, such as ski bindings, are designed to automatically release under extreme forces such as those experienced in a ski crash.
However, in some applications, it is desirable to restrain the orientation and position of the article in a way that enables easy installation and removal of the article without manual manipulation of a locking member or release member and without requiring an undue amount of force. In an example, it is often desirable to use a mounting system to mount an article such as a power tool like a miter saw onto a workspace. Such mounting system desirably restrains both the location and orientation of the power tool on the workspace, as movement or rotation may damage a workpiece or the tool, or injure a user. Such systems also desirably provide for easy installation and removal of the tool from the mounting system.
Various types of mounting systems for power tools have been developed. Generally, such mounting systems either completely restrain the tool, such as by using clamps, bolts, etc., thus requiring manual release of such restraints in order to remove the tool, or only partially restrain the tool, such as by drop-in mounts or groove-and-slide mounts which permit vertical and lateral motion respectively. Therefore, what is needed is a locking mechanism that automatically engages when an article is properly positioned, restrains the location and orientation of the article when engaged, and disengages without requiring use of a manual release.